GeoEvent Input "Poll an External Website for ...." Not Receiving Any Events

[#1]

Working with the following GeoEvent Inputs:

Poll an External Website for JSON

Poll an External Website for GeoJSON

Poll an External Website for XML

I've occasionally encountered that the input will not receive any events.  When adding the URL to a web browser it returns the data successfully, so why does it not when added to GeoEvent? 

The issue is most likely that the Acceptable MIME Types (Client Mode) parameter is not set correctly.  For example, I setup up the following Poll an External Website for JSON input:

It saves correctly, but when viewing the Input no events are coming through:

If the URL is added to a web browser, the correct information is returned:

The above was taken from FireFox.  Using the Web Developer tools included with FireFox I can find the MIME types that are used.  To do this click Ctrl+Shift+K to open the Web Console.  Click on the Network tab, and in the right panel click on Headers.  Under Request headers you will see the parameter Accept:

Copy this information and paste it in the Acceptable MIME Types (Client Mode) parameter for your input:

After saving the changes, the input now receives the events: